Cloth is manufactured from yarns containing fibers of various deniers by textile weaving or knitting processes or by the nonwoven techniques from natural or synthetic textile fibers and/or filaments made into yarns of the desired denier by conventional yarn making process. The natural and synthetic fibers are delivered to the yarn marking process as staple fiber in bales or as continuous filament on cones. In the case of the staple fiber, the yarn maker practices a process of opening wherein the staple fiber of a lot of bales is blended, by taking a small portion of each bale of the lot and passing it through a blend operation until the entire lot has been uniformly blended. The lot may be re-blended or cross-blended one or more times to increase the uniformity of the mixture of the fibers thus insuring more uniform yarn properties, such as dye acceptance. Depending upon the ultimate use of the yarn, various treatments may be undertaken at blending, such as tinting for lot identification or application of lubricants and the like. Usually, the blended fibers are fed into a card to produce a card sliver having a more parallel orientation of the fibers. It is customary to combine sliver from several cards in a process called drawing where the sliver strands receive a high degree of parallel orientation of the fibers in the sliver. Conventionally three drawing steps are employed, namely, breakers drawing, intermediate drawing and finisher drawing. The size of the sliver diameter is reduced in the next step called roving which further parallels the fibers and adds a small amount of twist. The roving is then ring spun into yarn. Alternatively, the roving from drawing may be spun into yarn by an open end spinning process. The yarn size produced is dictated by the ultimate end use of the yarn, e.g., the fineness of the ultimate weave and/or knit fabric
Of course when a continuous filament yarn is desired, several cones of the mono- or multi-filaments are used as received or may be twisted together to form the desired singles denier.
In both staple yarns and continuous filament yarn, if a ply yarn is desired, the usual custom is to twist two singles of yarn in a reverse twist to the singles twist to make the final denier or count of the yarn for knitting and/or weaving the cloth of the desired structure and weight.
The final treatment of the cloth is a series of washings, dyeing and pressing to finish the cloth for its ultimate use in clothing, sheeting and the like.
Many items of clothing made from cloth prepared as above described are worn by persons working in professions and arts where it is desirable or necessary to reduce the areas as the computer industry, both manufacture and use, it is desirable to reduce the accumulation of static charges on the cloth or person to a very low value to prevent glitches occurring in the circuitry resulting from the static discharge from the cloth of the wearer to the computer component and/or the computer per se. Current technology employs an organic polymer composite fiber, such as a nylon composite fiber, which is either a hollow fiber filled with a graphite paste or a fiber having a carbonaceous sheath about the exterior of the fiber. In either case, the resulting fibers, while electroconductive with respect to static-electrical dissipation, is of a larger than normal denier, that is, they have fiber diameters in the range of 20 to 50 microns, and may show up to the naked eye in the finished cloth. Further, the static dissipating fibers are not dyeable to the same degree as the other textile fibers with which they are blended and even in very dark fabrics may be noticeable.
While it may seem obvious to employ conventional carbon or graphite fibers it has been found that they are not suitable substitutes for the core or sheath yarns, since these carbon/graphite fibers or filaments having been carbonized at above about 1000.degree. C. are too brittle and break into such short staple during the yarn making process so that little or no static dissipating properties remain from their presence in the yarn.
It would therefore be advantageous for the cloth to be made static resistant and have electrical charge dissipating properties by incorporating into the cloth as a component of the yarn a finer denier, 7 to 20 microns, carbonaceous fiber having properties suitable for incorporation into the yarn per se during the yarn making process.